The invention discloses an optical diffusion membrane, which comprises a base material, and a main diffusion layer and a back diffusion layer which are formed on two surfaces of the base material. The parts are structurally characterized in that: the main diffusion layer is formed by coating and setting coating fluid containing optical dispersant, adhesive and cross linker on any one surface of the base material; the back diffusion layer is formed by coating and setting coating fluid containing optical dispersant, adhesive, an antistatic agent and cross linker on the other surface of the basematerial; the optical dispersant is spherical high polymer microspheres; the optical dispersant of the main diffusion layer comprises large granular optical dispersant and small granular optical dispersant, and the weight ratio of the large granular optical dispersant to the small granular optical dispersant is 11:1 to 7:1; and the grain diameter of the optical dispersant of the back diffusion layer is 1 to 5 microns. The optical diffusion membrane has sufficient optical diffusivity, and has good transmittance, good fog degree coordination, good scratch resistance and antistatic property.